Subscription validator

MoinMoin/storage/middleware/validation.py

 # Copyright: 2011,2012 MoinMoin:ThomasWaldmann
 # License: GNU GPL v2 (or any later version), see LICENSE.txt for details.
 
 """
 MoinMoin - validation for storage meta / data
 
 validation modes:
 
 trusted == False: for metadata coming from user input (like from web form) -
                   in this mode some values will be forced (e.g. mtime,
@@ skipping 300 matching lines @@
     if not isinstance(v, unicode):
         return False
     if len(v) != keys.HASH_LEN:
         return False
     try:
         int(v, 16)  # is this hex?
         return True
     except ValueError:
         return False
 
+
+def subscription_validator(element, state):
+    """
+    a subscription
+    """
+    try:
+        keyword, value = element.value.split(":", 1)
+    except ValueError:

[ana.balica, 2013/07/15 13:17:36]

For cases when there is no colon at all.

+        element.add_error("Subscription must contains colon delimiters.")
+        return False
+    if keyword in (keys.ITEMID, ):
+        pass
+    elif keyword in (keys.NAME, keys.TAGS, keys.NAMERE, keys.NAMEPREFIX, ):

[waldi, 2013/07/15 13:37:08]

Please actually read PEP-8!

[ana.balica, 2013/07/15 14:07:07]

I read http://www.python.org/dev/peps/pep-0008/ and no specific guides on how to
check if a value is in an iterable, tuple formatting, list vs tuple usages.
My best guess is to use a set instead of a list or tuple. if keyword in
{keys.NAME, }.
But didn't find anything on that too.
What should it look like?

+        try:
+            namespace, value = value.split(":", 1)
+        except ValueError:

[ana.balica, 2013/07/15 13:17:36]

Use case when there is a single colon and the keyword is not <itemid>.

+            element.add_error("Subscription must contain 2 colon delimiters.")
+            return False
+        namespace_element = String(namespace)
+        if not namespace_validator(namespace_element, state):
+            element.add_error("Not a valid namespace value.")
+            return False
+    else:
+        element.add_error(
+            "Subscription must start with one of the keywords: "
+            "'itemid', 'name', 'tags', 'namere' or 'nameprefix'.")
+        return False
+    value_element = String(value)

[waldi, 2013/07/15 13:37:08]

Please add some empty lines.

+    if keyword == keys.ITEMID:
+        value_is_valid = uuid_validator(value_element, state)
+    elif keyword == keys.TAGS:
+        value_is_valid = tag_validator(value_element, state)
+    elif keyword == keys.NAME:
+        value_is_valid = name_validator(value_element, state)
+    else:
+        value_is_valid = True
+    if not value_is_valid:
+        element.add_error("The value is not valid.")
+        return False
+    return True
+
+
 common_meta = (
     String.named(keys.ITEMID).validated_by(itemid_validator),
     String.named(keys.REVID).validated_by(revid_validator),
     String.named(keys.PARENTID).validated_by(uuid_validator).using(optional=True),
     String.named(keys.WIKINAME).using(strip=False).validated_by(wikiname_validator),
     String.named(keys.NAMESPACE).using(strip=False).validated_by(namespace_validator),
     List.named(keys.NAME).of(String.using(strip=False).validated_by(name_validator)).using(optional=True),
     List.named(keys.NAME_OLD).of(String.using(strip=False).validated_by(name_validator)).using(optional=True),
     Integer.named(keys.MTIME).validated_by(mtime_validator),
     String.named(keys.ACTION).validated_by(action_validator),
@@ skipping 30 matching lines @@
     String.named(keys.CSS_URL).using(optional=True),
     Integer.named(keys.RESULTS_PER_PAGE).using(optional=True),
     Integer.named(keys.EDIT_ROWS).using(optional=True),
     Boolean.named(keys.DISABLED).using(optional=True),
     Boolean.named(keys.WANT_TRIVIAL).using(optional=True),
     Boolean.named(keys.SHOW_COMMENTS).using(optional=True),
     Boolean.named(keys.EDIT_ON_DOUBLECLICK).using(optional=True),
     Boolean.named(keys.SCROLL_PAGE_AFTER_EDIT).using(optional=True),
     Boolean.named(keys.MAILTO_AUTHOR).using(optional=True),
     List.named(keys.QUICKLINKS).of(String.named('quicklinks')).using(optional=True),
-    List.named(keys.SUBSCRIBED_ITEMS).of(String.named('subscribed_item')).using(optional=True),
-    List.named(keys.SUBSCRIPTION_IDS).of(String.named('subscription_id')).using(optional=True),
+    List.named(keys.SUBSCRIPTIONS).of(String.named('subscriptions').validated_by(subscription_validator)).using(optional=True),
     List.named(keys.EMAIL_SUBSCRIBED_EVENTS).of(String.named('email_subscribed_event')).using(optional=True),
     #TODO: DuckDict.named('bookmarks').using(optional=True),
     *common_meta
 )
 
 
 def validate_data(meta, data):
     """
     validate the data contents, if possible
 
     :param meta: metadata dict
     :param data: data file
     :return: validation ok [bool]
     """
     ct = Type(meta[keys.CONTENTTYPE])
     if ct.type != 'text':
         return True  # we can't validate non-text mimetypes, so assume it is ok
     coding = ct.parameters['charset'].lower()
     if coding not in ['ascii', 'utf-8', ]:
         return True  # checking 8bit encodings this way is pointless, decoding never raises
     text_bytes = data.read()
     data.seek(0)  # rewind, so it can be read again
     try:
         text_bytes.decode(coding)
         return True
     except UnicodeDecodeError:
         return False